Many of Donald Trump’s critics claim he is unpredictable. In researching my article last year predicting Trump’s election win, I found the opposite to be true: Trump is relatively easy to predict if only one looks at what he says and understands that he believes what he says, contradictions and all.

Trump himself has stated that he not only believes that nuclear weapons could be used, but that they should be used. Small hands can still press a big red button.

I am not trying to suggest that I think Trump believes in nuclear armageddon. Even he would see the futility of a full scale nuclear clash. But what of the relatively small scale tactical nuclear weapons, if used against a commonly-perceived hostile state that is itself wishing to expand its nuclear technology? Could Trump, and those around him, rationalise the use of a small tactical weapon to wipe out an adversary’s nuclear facility, particularly if it were underground?

The US’s largest conventional weapon, the so-called “Mother of All Bombs”, recently failed to destroy cave complexes in Afghanistan. Could Trump be telling himself that a nuclear bomb is the only option left to his administration?

If you accept that Trump may be predisposed to using nuclear weapons, certainly more freely than any recent US leader, the obvious next question is against whom these weapons shall be used. Enter the two most likely suspects: North Korea and Iran.

Bombing North Korea has the risk of really upsetting the hermit kingdom’s neighbours. Both China and South Korea, for differing reasons, would react very negatively should there be an attack on Kim number three’s playground. Besides, Trump has clearly signalled that North Korea is China’s problem.

Iran, on the other hand, is bereft of neighbouring friends.

People in the West sometimes forget that Iran, while Islamic, is not Arab. Iran is Persian, and Arab-Persian antipathy pre-dates the arrival of Islam. It doesn’t take Egyptian Arabs long to remember the brutality of the ancient Persian kings, let alone look to the Islamic Shia and Sunni split.

Iran’s then president Mahmoud Ahmadinejad was one of the first foreign leaders to visit Morsi in Cairo, sending a chill down the spines of both Israel and Saudi Arabia. Neither the Wahhabist nor the Jewish State would see an Egypt-Iran rapprochement as in their interests. It had to be thwarted.

No surprise then, when the Saudis and Israelis both lobbied the Americans for an end to Morsi resulting in a “popular revolution” in Egypt, the ousting of Morsi and the election of a new secular general, Abd El-Fattah El-Sisi, who quickly attempted a gift of disputed islands to Saudi Arabia.

Iran and Saudi fight an economic war over oil supply and price. Iran needs an oil price north of $70 (£55) a barrel to balance their budget. Saudi will only agree to constricting supply and rise prices if the Iranians agree to their sanctions level output, limiting their revenue. Neither agree, so Opec is in stalemate. Oh my, the coincidences.

And if Trump were minded to drop a small tactical nuke to wipe out Iran’s nuclear facility, when would he do it? That depends. Does he need “Jim-Bob” in southern Arkansas to vote for the Republicans in the 2018 mid-terms, or vote for Trump in the 2020 Primaries? I think Iran has a little over two years.

I’ve travelled to both Iran and North Korea. I liked Iran. I found it a safe and friendly country; the biggest risk I experienced was either being swamped by hospitality or drowned in sweet tea. But today Iran is boxed in economically, militarily and politically. It has no friends left. Trump could drop a small nuke there and very few neighbours would bat an eyelid. Many would quietly applaud.

The nation has no allies. To prevent an attack it will likely need to either transparently drop its own nuclear programme or persuade Putin to step in on its behalf. Iran has reasons to be very worried indeed.